The influence of anode and cathode plasma upon the behavior of low‐impedance REB diodes is investigated by acquiring data with anodes and cathodes heated to 1000 and 200 °C, respectively. These data indicate a reduction in impedance collapse which is consistent with a 20% reduction in the anode‐cathode plasma gap closure velocity and a factor of 2.5 reduction in ion current. The ion current is reduced for heated anodes because then the ion current is primarily attributed to weakly ionized carbon and higher atomic number ions rather than protons.